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Tchnically you only have to go halfway down the list on average, which would make it O(0.5n), but by convention and for practicality purposes the notation drops and constant factors).

Again from NIST:

The unit of time, the second, was defined originally as the fraction 1/86 400 of the mean solar day. The exact definition of "mean solar day" was left to astronomical theories. However, measurement showed that irregularities in the rotation of the Earth could not be taken into account by the theory and have the effect that this definition does not allow the required accuracy to be achieved. In order to define the unit of time more precisely, the 11th CGPM (1960) adopted a definition given by the International Astronomical Union which was based on the tropical year. Experimental work had, however, already shown that an atomic standard of time-interval, based on a transition between two energy levels of an atom or a molecule, could be realized and reproduced much more precisely. Considering that a very precise definition of the unit of time is indispensable for the International System, the 13th CGPM (1967) decided to replace the definition of the second by the following (affirmed by the CIPM in 1997 that this definition refers to a cesium atom in its ground state at a temperature of 0 K):

The second is the duration of 9 192 631 770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the cesium 133 atom.

[1] Since the mid eighties the meter has actually been defined in terms of a fixed, integral number of wavelengths of light from a particular optical transition. Since the frequency of that optical transition is tied up in (what are believed to be fundamental) constants of nature, the speed of light is defined through this definition of the meter.

I had thought that the meter was defined as the distance light travels in 1/299792458 of a second, with the second being so many vibrations of a particular atom (cesium?).

Yep, according to NIST the length has been defined this way for quite some time:

The 1889 definition of the meter, based upon the artifact international prototype of platinum-iridium, was replaced by the CGPM in 1960 using a definition based upon a wavelength of krypton-86 radiation. This definition was adopted in order to reduce the uncertainty with which the meter may be realized. In turn, to further reduce the uncertainty, in 1983 the CGPM replaced this latter definition by the following definition:

The meter is the length of the path travelled by light in vacuum during a time interval of 1/299 792 458 of a second.

KB = kilobyte = 10^3 bytes = 1000 bytes
MB = megabyte = 10^6 bytes = 1000000 bytes
KiB = kibibyte = 2^10 bytes = 1024 bytes
MiB = mebibyte = 2^20 bytes = 1048576 bytes

This is a new standard designed to eliminate confusion, particularly as the discrepancy between powers of 2 and powers of 10 becomes very large when dealing with today's storage sizes (such as terabytes), and ensure that kilo and mega mean what they have traditionally done in science and every day life rather than the unofficial twisted computing adaptations.

MINOR CORRECTION: Others have claimed that MiB is a symbol/abbreviation of mibibyte. It's acutally mebibyte. The binary names always use the first two letters (first syllable) of the SI prefix.

• NIST Center for Neutron Research
• Los Alamos Neutron Science Center, Los Alamos
• High Flux Isotope Reactor, Oak Ridge National Lab
• Advanced Photon Source, Argonne National Lab
• Advanced Light Source, Lawrence Berkley Lab

If some of the terminology in this article gets too daunting, check out this online Dictionary of Algorithms, Data Structures, and Problems

If it's real, that is. It's one of those things that seems a little 'too good to be true', but when you look at Ferren's bio, it's highly believable.

See this link:

Biometric Consortium Bio of Bran Ferren

I'd have gone to new york to see this thing, but then I noticed that this already happened.

Why's it on slashdot so late?

How come selecting a unit of measure is somehow a government problem?

...was that OS X can handle filesizes up to eight exabytes—sorry, I forgot—that's eight exbibytes . More than a gigabyte for every man, woman & child on earth.

Okay, I'm satisfied. Now let's see some ATA10000 drives with that capacity, and I'll finally be able to reload all my MP3's.

In a press release issued earlier today, the National Institute of Standards and Technology has announced that they will be renaming the term "million" to "mebibillions". When asked what prompted the move, an NIST spokesman said, "Initially, it was due to the problem of accurately naming the number of lines of sourcecode some guy wrote for the benefit of RMS' ego. Its just plain silly how much this guy wrote." , later adding, "So, we came to a consensus within the organization that a revision to the basic units of measurement should be made, so it looks like we're busy so we don't lose our funding. In addition, we feel that marketing people should always determine standards, not the engineers and scientists who actually know what they're doing. Its just good sense." Beginning January 1st, the new "mebibillions" unit will take affect.

Mebibillions of people are expected to shake their heads in disbelief at the NIST's continuined stupidity.

:)
Cheers,

I would go for 'binary megabyte', though, instead of 'long megabyte'.

surprised that no-one has mentioned knuth's suggestion yet

i've mirrored knuth's discussion and suggestion for a solution below - link can be found here, on his news for 1999 page.

~~~~~~~mirrored text of donald knuth~~~~~~~~

Many people (and many online dictionaries) claim that a kilobyte (kB or KB) is 2^10 bytes, and that a megabyte (MB) is 2^10 kilobytes, etc.

I'm a big fan of binary numbers, but I have to admit that this convention flouts the widely accepted international standards for scientific prefixes.

Therefore I propose a simple way to resolve the dilemma and the ambiguity: Let us agree to say that

2^10 bytes is a large kilobyte, abbreviated KKB;

2^20 bytes is a large megabyte, abbreviated MMB;

and so on up the line: Large giga-, tera-, peta-, exa-, zetta-, and yottabytes are GGB, TTB, PPB, EEB, ZZB, and YYB, taking us up to 2^80. (Notice that doubling the letter connotes both binary-ness and large-ness.)

These proposals were motivated by the suggestions in 1995 of IUPAC-IDCNS (the International Union of Pure and Applied Chemistry's Interdivisional Committee on Nomenclature and Symbols), which were extended by IEC TC 25 (Technical Committee 25 of the International Electrotechnical Commission), chaired by Anders J. Thor. According to those committees, 2^20 bytes should be called a "mebibyte" and abbreviated MiB; 2^40 bytes should be called a "tebibyte" and abbreviated TiB; etc. The members of those committees deserve credit for raising an important issue, but when I heard their proposal it seemed dead on arrival --- who would voluntarily want to use MiB for a maybe-byte?! So I came up with the suggestion above, and mentioned it on page 94 of my Introduction to MMIX. Now to my astonishment, I learn that the committee proposals have actually become an international standard. Still, I am extremely reluctant to adopt such funny-sounding terms; Jeffrey Harrow says "we're going to have to learn to love (and pronounce)" the new coinages, but he seems to assume that standards are automatically adopted just because they are there. Surely a huge number of standards for other computer things, like networking protocols, have been replaced by better ideas when they came along. Thus I hope it still isn't too late to propose what I believe is a significantly better alternative, and I still think it unlikely that people will automatically warm to "mebibytes". Indeed, the last time I looked (June 28), names like "mebibyte.com" were being offered for sale but with no takers! I might, however, want to buy into a name like mmegabyte.com... And even in the unlikely event that mebibytes do catch on, MMB surely wins over MiB as their abbreviation. [See also the discussion by Kevin Walsh.]

When was it defined as a power of two? The meaning of mega, kilo, deca, hecto, pico, nano, femto etc. was defined as powers of two back in 1960, when the SI system of units was defined as a standard in the scientific world.

I think it's a kludge that kilo means 1024 in kilobyte, while it means 1000 in kilometer, kilogram, kilonewton, kilovolt etc. It's time we give it up, and accept correct terms. I agree kibi sounds ridiculous, but that's just a matter of habit. We'll get used to it.

Besides, not everywhere in CS kilo is 1024 and mega is 1024*1024: in datacommunications, the correct numbers are used. 10 mbit/s is 10000 bits per second.

When was it defined as a power of two? The meaning of mega, kilo, deca, hecto, pico, nano, femto etc. was defined as powers of two back in 1960, when the SI system of units was defined as a standard in the scientific world.

I think it's a kludge that kilo means 1024 in kilobyte, while it means 1000 in kilometer, kilogram, kilonewton, kilovolt etc. It's time we give it up, and accept correct terms. I agree kibi sounds ridiculous, but that's just a matter of habit. We'll get used to it.

Besides, not everywhere in CS kilo is 1024 and mega is 1024*1024: in datacommunications, the correct numbers are used. 10 mbit/s is 10000 bits per second.

This had to have been designed by somebody as a side-project, then was commercialized when "the higher-ups" heard of it. Really, why would you choose DES, unless you had the code already lying around, or something?

-Mark

No, the Metric system defines degrees Kelvin as it's standard unit of temperature. Look here and here

Seems like someone has understood something about patents. According to the Rijndael spec, the algorithm is not patented. Specifically, section 1 of the spec says:
Rijndael or any of its implementations is not and will not be subject to patents.
This should enable Free Software and Open Source Software projects to use the algorithm, and it seems some do already (like GnuPG). It would be interesting to know if the working group has considered patent issues when selecting an encryption algorithm for AES.

NIST required a reference implementation in C and two optimized implementations in C and old Java (JDK1.1). Reasonably good software benchmarks (even on 8-bit microprocessors) and probable hardware complexity were part of what they selected for.

I don't think that such an algorithm can be secure and have backdoors.

Cryptographic Module Validation Program is going to put that Backdoors?

I don't think that such an algorithm can be secure and have backdoors.

Cryptographic Module Validation Program is going to put that Backdoors?

The security of AES is currently being hailed as the fact it has a key field 10 to the 21 times larger than 56bit DES. Great. Only an idiot would try to brute force it though, so the number of keys is somewhat arbitrary.

Key length is, of course, vitally important. Understand the Rijndael spec. before you continue your speculation. Also, many "idiots" try to brute force it. Effort required to force a key is proportional to the cipher's weakness.

Less generally, by employing lack of symmetry and a non-linear layer in the cipher, AES pretty much gurantees that you'll simply be searching the key-space at random. If you can come up with a way to do better than a brute force, you should quit your current job.

The 2^255 Rijandel iterations required to force a 32 byte key is certainly sufficiently secure by todays standards, but historically consistent increases in computing power coupled with increased distributed processing ability due to networked computer proliferation means that keys will have to keep growing to stay resonably secure.

> There a big ambiguity that I couldn't really sort out while reading these web pages : Is this an Open standard or a Commercial standard ?

It's a US government standard, meaning that all government-related (whatever that means) should use it (or something like that). It's just another algorithm instead of DES/3DES to be used as The Official US Government Encryption Standard.
Some pieces-o'-software, both free and commercial, use Rijndael, but it's not a standard (ISO or ANSI or whatever).

> Will I have to pay royalties if I intend to write AES-compliant programs then sell related services ?

Probably not. There are plenty of free implementations of the Rijndael algorithm, and from what I can figure out, there doesn't seem do be any restrictions to it. From the authour's page:
Rijndael is available for free. You can use it for whatever purposes you want, irrespective of whether it is accepted as AES or not.

Even if the US government puts some kind of export restriction on software using it, it's still very available (in several free (of some kind) implementations) outside US.
NIST too, provide their own reference implementation.

> I actually read in the facts page that the "public" helped building the algorithm and specs but in which way is that AES thing public ?

The algorithm was invented by "the public" (two guys in Belgium), not by NIST or the US government. NIST just selected the one algorithm they considered the most appropriate from the whole lot of available encryption algorithms out there.

> There a big ambiguity that I couldn't really sort out while reading these web pages : Is this an Open standard or a Commercial standard ?

It's a US government standard, meaning that all government-related (whatever that means) should use it (or something like that). It's just another algorithm instead of DES/3DES to be used as The Official US Government Encryption Standard.
Some pieces-o'-software, both free and commercial, use Rijndael, but it's not a standard (ISO or ANSI or whatever).

> Will I have to pay royalties if I intend to write AES-compliant programs then sell related services ?

Probably not. There are plenty of free implementations of the Rijndael algorithm, and from what I can figure out, there doesn't seem do be any restrictions to it. From the authour's page:
Rijndael is available for free. You can use it for whatever purposes you want, irrespective of whether it is accepted as AES or not.

Even if the US government puts some kind of export restriction on software using it, it's still very available (in several free (of some kind) implementations) outside US.
NIST too, provide their own reference implementation.

> I actually read in the facts page that the "public" helped building the algorithm and specs but in which way is that AES thing public ?

The algorithm was invented by "the public" (two guys in Belgium), not by NIST or the US government. NIST just selected the one algorithm they considered the most appropriate from the whole lot of available encryption algorithms out there.

Hi, I appreciate the thought that went into your comment but I thinked you've assumed unlicensed == unregulated which is not true. Equipment in the 2.4 ISM band is regulated, devices have strict power restrictions and behavior ettiquette that they must follow, backed by the force of law. If the regulations are not sufficient for a target application then government needs to come up with regulatory regimes that are in partnership with industry. And that's exactly what's happening.

License free (open, if you will) 900mhz and 2.4ghz are a different model of spectrum regulation resulting from equipment manufacturers (particularly apple in the 802.11b case), rather than content providers, taking the lead in working with government to work out the regs and in the standards bodies. The new NII band in 5ghz is a refinement of this process, a new partnership of government and industry centered around open standards. Heck a member of NIST's NWEST group is the chair of the 802.16 working group. The kinds of partnerships that are taking place are very much like those that the open source community are looking for in advancing its movement, as Benkler's writings will bear out.

I'd be interested to hear what you thought of the technical papers that I reference, or the work of the 802.16 working group to hear if they address any of your concerns.

This group has some misconceptions about the FIPS 140 process. First, they rightly point out that the level 4 cert on the IBM 4758 does not cover the CCA software, and then they go on to talk about how a bug in this (admittedly, non-evaluated software) shows the weakness of FIPS 140-1.

Hmm... Well, interesting, but wrong. First, as they point out, the CCA software is not covered by the FIPS cert. Once you install the CCA software on the 4758, the 4758 is no longer a FIPS 140-1 module, level 4 or otherwise. The FIPS cert only applies to the module as it was evaluated. As this post's parent points out, the 4758 allows arbitrary code to be uploaded into the module. This means that as soon as you load unevaluated (ie: non-FIPS 140-1 evaluated) code into the module, it looses its FIPS 140-1 level 4 status.

So, what is evaluated? Examining the NIST FIPS 140 validated modules list you'll see there are several pertinent certificates that apply to the IBM 4758 card. First, there is the level 4 certification of the 4758 and the boot code (Miniboot layers 0 and 1) (certificates # 35 and 116). Next you see the FIPS 140-1 level 3 certificates involving the 4758 with its onboard OS (CP/Q++) at layer 2 (certificates #122, 122). Note that as soon as you add the OS the certification drops to at most level 3. And that's without any application code at all; no CCA, no other libraries, and no applications.

You'll also note, that the CCA is not evaluated under any of these certificates. If you think that this is an oversight on IBM's part, I have a lovely patch of land to sell you.

Now, just to put all this 4758 bashing into perspective: The IBM 4758 is an amazingly secure cryptographic module. It is by far the most well designed and implemented cryptographic module I have ever worked with, and that says a hell of a lot. Sure, there may be more secure modules out there, but not in the civilian market. The 4758 is, to put it plainly, The Shit. The reason this module is such an interesting target is that it defines the state of the art of cryptographic modules. To put it another way, virtually every other cryptographic module (software or hardware) is less secure than the IBM 4758.

When someone demonstrates a possible attack against an IBM 4758, you shouldn't just say to yourself "Oh, this doesn't matter, I don't own/use/deal with one of these". Because the IBM 4758 is the commercial state of the art, the work factor associated with breaking every other cryptographic module out there is less. So, if it only takes an a few days compromise the 4758, it is a fairly good bet that it takes less time than that to compromise any other commercial cryptographic module.

Ain't it grand?

Well, according to the IEC standard, one petabyte is 10^15 (or 1e+15) bytes, while one pebibyte is 2^50 (or 1.125899e+15) bytes.

So 144 petabytes is 1.44e+17 bytes or 127.89769 pebibytes. Can't say that's more impressive tho. :P

It's interesting that you brought this up, but really there is no ambiguity in the terminology only in how its used. Here is a good site for helping you out with all those binary multiples.

JOhn

Are you saying that there is no such thing as a Hydrogen Molecule?

You can also check out the Uranium Molecule hits I've seen.

Just because it's an element doesn't mean it doesn't have a molecule made up of more than one atom. (Oxygen molecules and Ozone come to mind.)

"They *shouldn't* be, and true standards do not evolve much, if at all.

"Imagine if a kilogram was 2.2lb one day, then 4.3lb the next. Not much of a "standard", is it?"

Of course, the "standard" of the kilogram evolves too. As posted on Slashdot six weeks ago, NIST is seeking an electronic kilogram rather than a hunk of metal.

Saying something changed doesn't indicate if it got better or worse. Merely that it is different. I think the purpose of a standard is to enable people to know that if they want to accomplish X, following steps 1, 2, . . . n will do that. But if they want to do Y or if there is a better way to do X, the standard needs to change. The point of having standards is to do other things. If all you care about is the standard, you can just use tautologies: "A light year is the distance traveled by light in a year."

This project is actualy quite simple, a room, some cameras, some microphones, you, a meeting and all on disk and/or live, with or without being process through some filters, ... This while at the same time using and evaluating commercial tools to use our data transfer "SmartFlow" ... and all of that on plenty of Linuxes ... cute I think ? ;)

More details at http://www.nist.gov/smartspace/

You really don't get it, do you? "second" is not short for anything.

"The second is the duration of 9 192 631 770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the cesium 133 atom."
from: http://physics.nist.gov/cuu/Units/current.html

The base unit of time is called "second", not "second of time" or "second minute". Let me repeat that: "second" is a unit. It implies that the number which it qualifies is meant to be an amount of time. The term "second" is also part of the names of other units. That does not make the convention invalid that, when used precisely, a second is always a duration (and never an angle, for example).

I begin to understand how there can be people at NASA fucking things up the way they did.

H = m^2kg/(s^2A^2)

H/m = m^2kg/(s^2A^2m) = mkg/(s^2A^2)
A^2 = mkg/(s^2(H/m)) = m^2kg/(s^2H)

1. y = x + 1 (look! y is a function of x!)
2. x = y - 1 (gasp! now x is a function of y!)

Isn't this a dead give-away. System = collection of units used together: International = hodgepodge designed to clip the wings of foreign aspirations. Enough said

WTF are you talking about? Care to explain this? Obviously not enough said.

Actually, you would more easily understand the intensity of a kilometre-candle, (ie a candle at a kilometre), rather than a metre-microcandle, (ie a millionth of a candle at a metre), which is what a microlux is all about.

Of course, had you any idea what you were talking about, you'd know that microlux is not an SI unit. The candela (cd) is the unit of luminous intensity.

Also, an acrefoot is an easier volume to grasp than a Megalitre, although they're the same size.

An acrefoot? lol. Ya, that's real intuitive for people who have heard of neither acres, nor feet. Also, once again if you knew what you were talking about, you'd have known that the liter isn't an SI unit either. Volume is measured in cubic meters which is very easy to grasp.

People convert sheets of paper into stacks miles high because thousands and millions can not be grasped.

Perhaps for simple minds. You telling me you can't grasp 1 million dollars?

They only have seven, because the the system is a botch-up that they HAD to have 7.

No, you see it's called good design. You put something in if it makes sense that it should be there, because it is, in fact, a distinct entity.

The mole was only invented as a base because SI did not want to use the coherent kilomole.

Source please? Or were you just talking out of your ass (again) ?

The base unit "Ampere" depends on the size of the metre and kilogram, but the "Henry per metre" is free of such dependancies.

The Ampere does not depend on meters and kilograms. In fact, it depends on no other units, hence the reason it is a base unit. Perhaps you might care to explain why you believe this? Furthermore, Henry per meter is not free of dependency on meter or kilograms. The henry is m^2kg/(s^2A^2), therefore the "Henry kilogram per meter squared" is free of them.

Yet the "Ampere is afforded the status of "base unit". The size of the candela depends on the square metre, but the lux does not.

Once again, you seem to confuse base unit with derived units. The candela is base, and therefore independent of all other units. The lux is derived and is defined as: cd/m^2.

Some is the operative word here. Rationalisation throws a spanner in the works. 1 C translates into 12.566 C, if flux is being refered to.

I'm sorry, care to clarify your incredibly vague point? The flux of coulombs? Also, perhaps you should keep in mind that an entity and it's flux are distinct and so should be different. I think you are confused.

The pre-metric system used by scientists was Paris feet. Not having a precise widely used measurement system does not hinder much of science.

And you would know this... how exactly?

Why measure volumes in litres. Doesn't the cubic metre cope with this??? No.

Yes actually. Volume is not measured in liters, but in cubic meters.

And from this, we can see immediately how "Weber" is derived from "Metre", "kilogram", "second", and "ampere". Get real.

He said sticking to the letter, ie. using m^2kg/(s^2A^1) instead of Weber. Perhaps you should try reading next time. You know: left to right, top to bottom, group words into sentences, take tylenol for any headaches.

Furtermore, you fail to demonstrate a superior and more consistent system. Are we just supposed to believe your word that SI sucks and that anything else is better? Considering that you've made a fool of yourself in this post by trying to criticize something of which you apparently know very little, you now have zero credibility. So why should anyone listen to you? In the unlikely case you'd like to abolish your ignorance, try this page which outlines SI quite well.

Have a nice day!

It is already being used in autonomous robots for its superiority over sonar at Helpmate with funding from NIST, for use in hospital robots.

No, it would not be better to use Flash instead of Java.

Java applets have two big advantages over plugins:

• Java is generic. Java applets can do pretty much anything, but you need to get a new plugin for each new task.
• They are platform-independent.

The new standard is going to be "the ammount of mass properly balanced by XXX volts and YYY amperes in the referenced system."

SI standards based on absolute numbers (as opposed to chunks of metal) include the second (9192631770 ticks of a cesium atom) and the meter (the distance light travels in 1/299792458 second). But you can't define kilogram in terms of volt or ampere because they're already based on the kilogram. A volt is one watt per ampere. A watt will raise a 1N weight at 1m/s, while a newton will accelerate a 1kg mass at 1m/s^2. An ampere is the current in two parallel wires 1m apart that produces 2e-7N per meter of length. Therefore, defining a kilogram in terms of a volt or ampere would be circular (unless NIST skillfully arranges the equation to solve for kg); NIST must define its new version of the kilogram in terms of the second and meter.

Sources include NIST's current definitions.

Similarly, the kg could be defined as "the mass of 4.32415234895 x 10^33 protons (or whatever -- pulled that number out of you know where).

There's nothing "circular" about that definition at all.

Explaining it even better:

Taken from: Nist Home page
'The kilogram is the only remaining SI base unit whose definition is based on a physical artifact rather than on fundamental properties of nature.'

I guess that the mass of a proton can be defined as a properties of nature.

Second: The second is the duration of 9 192 631 770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the cesium 133 atom.

As mass and energy are equivalent, can't they just define the mass as a certain number of barrels of that cesium 133 light? Right now they just throw away that light each second, but they could recycle it.

Second: The second is the duration of 9 192 631 770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the cesium 133 atom.

As mass and energy are equivalent, can't they just define the mass as a certain number of barrels of that cesium 133 light? Right now they just throw away that light each second, but they could recycle it.

Second: The second is the duration of 9 192 631 770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the cesium 133 atom.

As mass and energy are equivalent, can't they just define the mass as a certain number of barrels of that cesium 133 light? Right now they just throw away that light each second, but they could recycle it.

By the way, here is a photo of the artifact. It's been kept under specified conditions since 1889.

Hmmm - which unfortunately comes back to a density of photons, and a length cubed, which unforteunalty comes back to that damn platinum bar in Paris. IIRC - it has a chip in the corner of it too - Ooops. I just dropped your metre - my, how you have just grown!

Now of course we could explain a kilogram to the alien in terms of something else it's probably got lying around, such as carbon atoms or electrons, but then the precision would be limited by our own measurements, and we wouldn't be conveying "the standard".

Go here to check it out. Incidentally, can someone explain to me why the mole is a base unit?

A kilogram is a unit of mass not weight. Weight is dependant on gravity. Mass is not.

True enough, but if you want to determine the mass of a small object, how do you do it? Odds are really good you're going to weigh it in some manner, and divide by 9.8 m/s^2.

According to NIST, they've got a variance on the order of 3% per century in the observed mass (probably measured by weight) of the standard kilo brick.

Wow! I thought the recent news of observations that show that the fine structure constant or the speed of light may be minutely changing as the universe ages were pretty far out, but to think that mass is this variable...

"They balance it against gravity to measure it?"

The article linked to makes it sound that way, but if you have an electronic measurement for force (which is what the "electronic kilogram" is - see the excellent page posted by aktbar), and you have other standards for the meter (certain number of wavelengths of a certain light) and second (certain vibration of some molecule, I'd have to look up the details), then F=ma (force = mass times acceleration) lets you derive the kilogram. (in units terms, Newtons = kilograms times (meters per second squared) - if you have newtons, meters, and seconds, then you get kilograms).

"Sheeze, why not just define it as 1.498e20 atoms of carbon"

This approach has also been investigated. See the Avogadro Group or an article summarizing it. These things boil down to what you can measure more accurately.

"They balance it against gravity to measure it?"

The article linked to makes it sound that way, but if you have an electronic measurement for force (which is what the "electronic kilogram" is - see the excellent page posted by aktbar), and you have other standards for the meter (certain number of wavelengths of a certain light) and second (certain vibration of some molecule, I'd have to look up the details), then F=ma (force = mass times acceleration) lets you derive the kilogram. (in units terms, Newtons = kilograms times (meters per second squared) - if you have newtons, meters, and seconds, then you get kilograms).

"Sheeze, why not just define it as 1.498e20 atoms of carbon"

This approach has also been investigated. See the Avogadro Group or an article summarizing it. These things boil down to what you can measure more accurately.

"They balance it against gravity to measure it?"

The article linked to makes it sound that way, but if you have an electronic measurement for force (which is what the "electronic kilogram" is - see the excellent page posted by aktbar), and you have other standards for the meter (certain number of wavelengths of a certain light) and second (certain vibration of some molecule, I'd have to look up the details), then F=ma (force = mass times acceleration) lets you derive the kilogram. (in units terms, Newtons = kilograms times (meters per second squared) - if you have newtons, meters, and seconds, then you get kilograms).

"Sheeze, why not just define it as 1.498e20 atoms of carbon"

This approach has also been investigated. See the Avogadro Group or an article summarizing it. These things boil down to what you can measure more accurately.

(one of) NIST's own web page(s) on this is at http://www.eeel.nist.gov/811/elec-kilo.html. There's a lot more technical detail there than at the link given in the article.

This really does make sense to replace the artifact with something independent -- they have a bunch of "voodoo" every time they measure the current kilo to try to get the same answer.

If nothing else,
32 bits = 4 gigabytes of addressable memory
64 bits = 16 exabytes of addressable memory

And in case you need help with the SI units, click here.

What does someone need 16 exabytes of memory for right now, I don't know, but there are applications that might need more than 4 gigabytes of memory. (For example, data warehouses.)

(I think I did the math right for the amounts of memory, but feel free to check for yourself.)